LEDs are a type of semiconductor light-emitting element. With a view to energy conservation, in recent years a lamp (hereafter, “LED lamp”) using LEDs as a light source has been proposed as a bulb-type lamp that is an alternative to an incandescent light bulb.
The LED lamp includes a plurality of LEDs, a mounting board, a case that is cylindrically shaped, a cover member that closes one end of the case, and a circuit unit that enables the LEDs to emit light. The LEDs are mounted on the mounting board, the mounting board is installed on a surface of the cover member, and the circuit unit is fitted inside the case (Patent Literature 1).
In the LED lamp disclosed in Patent Literature 1, the cover member has a function of conducting heat generated when the LEDs emit light to the case, and the case has a heat dissipation function of dissipating heat that is conducted from the cover member. Thus, the cover member and the case are formed from metal material having a high thermal conductivity, and the cover member and the case are joined in contact with each other.
In order to ensure that the circuit unit is in an insulated state inside the case, a resin housing that houses the circuit unit is provided inside the case. Thus, the circuit unit is isolated from the case. The resin housing consists primarily of a main part that is cylindrical and houses the circuit unit, and a cover part that closes an opening at one end of the main part. The cover part is attached to the cover member by using a screw.